CEA Human Factors Engineering 2 — Questions and Answers
Question 1: Which signal detection theory measure reflects a person's ability to discriminate a signal from noise, independent of response bias?
- Beta
- d-prime (d') (Correct answer)
- Hit rate
- False alarm rate
Correct answer: d-prime (d')
d-prime (d') is the sensitivity index in signal detection theory that measures discriminability independent of the observer's decision criterion.
Question 2: The Fitts' Law formula MT = a + b log2(2A/W) predicts movement time based on which two variables?
- Speed and accuracy
- Amplitude and target width (Correct answer)
- Reaction time and movement distance
- Muscle strength and fatigue
Correct answer: Amplitude and target width
Fitts' Law predicts movement time using amplitude (distance to target) and target width, where a wider target or shorter distance reduces movement time.
Question 3: Which memory system has the largest capacity and longest duration but requires encoding for information to be retained?
- Sensory memory
- Working memory
- Long-term memory (Correct answer)
- Procedural buffer
Correct answer: Long-term memory
Long-term memory has virtually unlimited capacity and indefinite duration, but information must be encoded through rehearsal or meaningful association.
Question 4: In human factors, 'situation awareness' (SA) is best defined as:
- The operator's ability to multitask efficiently
- Perception, comprehension, and projection of environmental elements (Correct answer)
- A measure of reaction time in dynamic environments
- The skill of avoiding cognitive tunneling
Correct answer: Perception, comprehension, and projection of environmental elements
Mica Endsley's model defines SA as three levels: perception of elements, comprehension of their meaning, and projection of future status.
Question 5: The 'population stereotype' concept in human factors refers to:
- Demographic assumptions used in task analysis
- The expected direction of control movement that most people intuitively associate with a display change (Correct answer)
- Average anthropometric dimensions for a given population
- Biases introduced by stereotype threat in usability testing
Correct answer: The expected direction of control movement that most people intuitively associate with a display change
Population stereotypes describe the control-display movement relationships that a majority of users expect, such as turning a knob clockwise to increase a value.
Question 6: Which cognitive bias causes operators to search for information that confirms their initial hypothesis while ignoring contradictory evidence?
- Anchoring bias
- Confirmation bias (Correct answer)
- Availability heuristic
- Framing effect
Correct answer: Confirmation bias
Confirmation bias leads operators to selectively attend to data supporting their initial diagnosis, potentially delaying recognition of the true problem.
Question 7: In the context of mental workload assessment, the NASA-TLX tool measures workload across how many subscales?
- 3
- 4
- 6 (Correct answer)
- 8
Correct answer: 6
The NASA Task Load Index (NASA-TLX) uses six subscales: Mental Demand, Physical Demand, Temporal Demand, Performance, Effort, and Frustration.
CEA Human Factors Engineering 2
Which signal detection theory measure reflects a person's ability to discriminate a signal from noise, independent of response bias?